1. Field of the Invention
This invention relates to a lubricating device, and, more particularly, it is concerned with a device utilizing a compressive or non-compressive fluid fed from an external pressure device for lubrication of two opposing surfaces which move relatively.
2. Description of the Prior Art
Heretofore, a hydrostatic bearing using a compressive fluid such as air has been utilized in precision machine tools, and a hydrostatic slider has also been employed in various measuring instruments and forwarding mechanism in machine tools. The reason for this is that, in comparison with contact type sliders, in which rollers and metal parts are directly contacted with each other in operation, the abovementioned fluid slider is of the type which does not contact with a supporting member, hence smooth operation can be secured with the least friction between them and precision in machining work can be increased. On the other hand, however, the fluid bearing and slider inherently possess various disadvantages such that they are inferior in load sustaining capability in comparison with the contact type bearing, and that the bearing action becomes unstable when a gap between the bearing and the supporting member becomes widened in case a compressive fluid such as air is used in particular, as the result of which the so-called self-excited vibrations, wherein the bearing vibrates in the up and down direction, tend to occur readily.